PADOS PC-based patient dosimetry system

A PC-based activity measurement system for patient monitoring of a radio-therapy ward.
Because of radiation protection regulations it is e.g. only allowed to perform the I-131 therapy under stationary conditions.
The release of a patient from stationary treatment after application of open radioactive materials and/or sources in the body is only allowed, if the radiation exposure for other persons does not exceed 1 mSv/h.
For I-131 this means that the equivalent dose rate on the day of release on 2 m distance doesn’t exceed 3.5 µSv/h. This corresponds to a rest activity of approx. 250 MBq.
The PADOS system makes it possible to measure and register the current activity and/or the dose rate of the resting patient periodically.
For measurement, a detector collimated for the area is mounted over the bed. The measurement data are analysed and stored by the PC-system.
Based on the periodically registered data, the system software calculates the expected moment of falling below the limit value as date for the patient’s release.
In this way, an optimized bed planning for the therapy ward is possible.
Thanks to the automatic measuring value registration, the measuring system can be used by the treating physician or the nursery personnel to reduce their radiation exposure.
The detector unit which is mounted over the patient’s bed contains the detector incl. detector electronics with serial RS 485 interface.
The detector is a scintillation detector (NaI). It is integrated in a shielding and is collimated for the patient’s position.
In this way, the mutual influence of the measuring values in case of double rooms is reduced to the minimum.

monitor pados
bed I-131 patient<br />bed I-131 patient